Mating Type of Potato Phytophthora infestans of Gansu and Their Sensitivity to Metalagl

The isolates were assessed for mating type and sensitivity to Metalaxyl of potato Phytophthora infestans were collected from Gansu province from 2007 to 2009.Among 79 isolates were tested for mating type,69 isolates belonged to A1 mating type,4 were A2 mating type,6 were selffertil mating type.The 117 isolates were inspected for sensitivity to Metalaxyl.The results showed that 60.68% were highly resistance,11.97% were intermediate resistance,27.35% were sensitive.